[Title 40 CFR 60.281]
[Code of Federal Regulations (annual edition) - July 1, 2009 Edition]
[Title 40 - PROTECTION OF ENVIRONMENT]
[Chapter I - ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)]
[Subchapter C - AIR PROGRAMS (CONTINUED)]
[Part 60 - STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES--]
[Subpart Bb - Standards of Performance for Kraft Pulp Mills]
[Sec. 60.281 - Definitions.]
[From the U.S. Government Printing Office]


40PROTECTION OF ENVIRONMENT62009-07-012009-07-01false60.281Sec. 60.281PROTECTION OF ENVIRONMENTENVIRONMENTAL PROTECTION AGENCY (CONTINUED)AIR PROGRAMS (CONTINUED)STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES--Standards of Performance for Kraft Pulp Mills
Sec. 60.281  Definitions.

    As used in this subpart, all terms not defined herein shall have the 
same meaning given them in the Act and in subpart A.
    (a) Kraft pulp mill means any stationary source which produces pulp 
from wood by cooking (digesting) wood chips in a water solution of 
sodium hydroxide and sodium sulfide (white liquor) at high temperature 
and pressure. Regeneration of the cooking chemicals through a recovery 
process is also considered part of the kraft pulp mill.
    (b) Neutral sulfite semichemical pulping operation means any 
operation in which pulp is produced from wood by cooking (digesting) 
wood chips in a solution of sodium sulfite and sodium bicarbonate, 
followed by mechanical defibrating (grinding).
    (c) Total reduced sulfur (TRS) means the sum of the sulfur compounds 
hydrogen sulfide, methyl mercaptan, dimethyl sulfide, and dimethyl 
disulfide, that are released during the kraft pulping operation and 
measured by Method 16.
    (d) Digester system means each continuous digester or each batch 
digester used for the cooking of wood in white liquor, and associated 
flash tank(s), blow tank(s), chip steamer(s), and condenser(s).
    (e) Brown stock washer system means brown stock washers and 
associated knotters, vacuum pumps, and filtrate tanks used to wash the 
pulp following the digester system. Diffusion washers are excluded from 
this definition.
    (f) Multiple-effect evaporator system means the multiple-effect 
evaporators and associated condenser(s) and hotwell(s) used to 
concentrate the spent cooking liquid that is separated from the pulp 
(black liquor).
    (g) Black liquor oxidation system means the vessels used to oxidize, 
with air or oxygen, the black liquor, and associated storage tank(s).
    (h) Recovery furnace means either a straight kraft recovery furnace 
or a cross recovery furnace, and includes the direct-contact evaporator 
for a direct-contact furnace.
    (i) Straight kraft recovery furnace means a furnace used to recover 
chemicals consisting primarily of sodium and sulfur compounds by burning 
black liquor which on a quarterly basis contains 7 weight percent or 
less of the total pulp solids from the neutral sulfite semichemical 
process or has green liquor sulfidity of 28 percent or less.
    (j) Cross recovery furnace means a furnace used to recover chemicals 
consisting primarily of sodium and sulfur compounds by burning black 
liquor which on a quarterly basis contains more than 7 weight percent of 
the total pulp solids from the neutral sulfite semichemical process and 
has a green liquor sulfidity of more than 28 percent.
    (k) Black liquor solids means the dry weight of the solids which 
enter the recovery furnace in the black liquor.
    (l) Green liquor sulfidity means the sulfidity of the liquor which 
leaves the smelt dissolving tank.
    (m) Smelt dissolving tank means a vessel used for dissolving the 
smelt collected from the recovery furnace.
    (n) Lime kiln means a unit used to calcine lime mud, which consists 
primarily of calcium carbonate, into quicklime, which is calcium oxide.
    (o) Condensate stripper system means a column, and associated 
condensers, used to strip, with air or steam, TRS compounds from 
condensate streams from various processes within a kraft pulp mill.

[43 FR 7572, Feb. 23, 1978, as amended at 51 FR 18544, May 20, 1986; 65 
FR 61758, Oct. 17, 2000]